The question then remained: what was the exact time Twitter went through the half billion mark?

To get this after the fact was, however, quite easy. We merely pulled user number 500 million from the Twitter API, and looked at the exact time of registration. This came down to:

22 February 2012 18:06:05 GMT

Ok, but that’s not the interesting part. The real interesting question is: who is this user number half billion?

Piotr Janicki is a predominantly male name, so our user is most likely male. He hasn’t tweeted yet, and is from Warsaw (or at least from that time zone). He follows 6 people, and 11 people follows him back (including us). He’s probably completely oblivious of the fact, but his Twitter ID has a huge amount of geek value!

We’ve contacted Piotr via @message on twitter, to see if he’s up for an interview. If he responds, you’ll be the first to know.